School of Cognitive Sciences, Institute for Research in Fundamental Sciences (IPM), 19395-5747, Tehran, Iran.
Brain Res. 2010 Mar 12;1320:143-51. doi: 10.1016/j.brainres.2010.01.022. Epub 2010 Jan 18.
Previous research has suggested that Parkinson's disease (PD) impairs motion perception. First-order motion consists of moving luminance-defined attributes. Second-order motion, on the other hand, consists of moving patterns whose motion attributes are not luminance-defined. The detection of first and second-order motion is thought to be mediated by different mechanisms. Here, we compare the ability of Parkinson's disease patients (PDPs) to detect first-order/second-order motion with normal subjects. Subjects had to discriminate the drift direction of first-order motion (luminance-modulated noise) and a second-order motion pattern (named as noise base motion) over a range of stimulus speeds and strengths. Results show that the first-order motion detection deficits could only be seen with lower motion strengths suggesting a ceiling effect with higher motion strengths. However, second order motion detection deficits were seen across high and low motion strengths, suggesting that the second order motion detection may be more affected in PD than the first-order motion detection. Our results indicate that higher-level visual cortex plays an important role in PD patients' disabilities in motion perception.
先前的研究表明，帕金森病（PD）会损害运动感知能力。一阶运动由运动的亮度定义的属性组成。二阶运动则由运动属性不是亮度定义的运动模式组成。据认为，一阶和二阶运动的检测是由不同的机制介导的。在这里，我们比较了帕金森病患者（PDPs）和正常受试者检测一阶/二阶运动的能力。受试者必须在一系列刺激速度和强度下辨别一阶运动（亮度调制噪声）和二阶运动模式（称为噪声基运动）的漂移方向。结果表明，只有在较低的运动强度下才能看到一阶运动检测的缺陷，这表明在较高的运动强度下存在上限效应。然而，二阶运动检测的缺陷在高、低运动强度下都能看到，这表明二阶运动检测在帕金森病患者中比一阶运动检测受到的影响更大。我们的结果表明，高级视觉皮层在帕金森病患者的运动感知障碍中起着重要作用。
